MLKitDigitalInkRecognition Framework Reference

MLKDigitalInkRecognizer


@interface MLKDigitalInkRecognizer : NSObject

Object to perform handwriting recognition on digital ink.

Digital ink is the vector representation of what a user has written. It is composed of a sequence of strokes, each being a sequence of touch points (coordinates and timestamp). See Ink for details.

  • Unavailable. Use digitalInkRecognizer(options:) instead.

    Declaration

    Objective-C

    - (nonnull instancetype)init;
  • Creates a DigitalInkRecognizer object using the specified options.

    See DigitalInkRecognizerOptions for details.

    Declaration

    Objective-C

    + (nonnull MLKDigitalInkRecognizer *)digitalInkRecognizerWithOptions:
        (nonnull MLKDigitalInkRecognizerOptions *)options;
  • Performs a recognition of the input ink.

    Note that using recognize(ink:context:completion:) instead of this method may lead to better accuracy in some cases.

    Declaration

    Objective-C

    - (void)recognizeInk:(nonnull MLKInk *)ink
              completion:(nonnull MLKDigitalInkRecognizerCallback)completion;

    Parameters

    ink

    Input to be recognized.

    completion

    A callback for returning recognition candidates. See DigitalInkRecognizerCallback for details.

  • Performs a recognition of the input ink using a recognition context.

    A recognition context contains information about the size of the writing area, and the characters that have already been entered in the text area. This helps disambiguate certain cases.

    Example usage: a previous recognition has yielded the string “hello”, that has been inserted in a text field. The user then handwrites “world”. Send the present method the ink showing “world”, and “hello” as a string in context. The recognizer will most likely return the string “ world” with a leading space separating the two words.

    See DigitalInkRecognitionContext for details.

    Declaration

    Objective-C

    - (void)recognizeInk:(nonnull MLKInk *)ink
                 context:(nonnull MLKDigitalInkRecognitionContext *)context
              completion:(nonnull MLKDigitalInkRecognizerCallback)completion;

    Parameters

    ink

    Input to be recognized.

    context

    See DigitalInkRecognitionContext for details.

    completion

    A callback for returning recognition candidates. See DigitalInkRecognizerCallback for details. If nothing can be recognized, an empty list of candidates will be passed to the callback.